1. Field of the Invention
The present invention relates to a recording device having a transport mechanism for transporting a recording medium such as a sheet of paper on which a recording head performs recording.
2. Description of the Related Art
In general, ink-jet recording devices perform recording on a recording medium by allowing a recording head to discharge flying ink drops. Such recording devices have various advantages such as an easy reduction in the size of the recording head, performing accurate and high-speed recording, a low running cost, low noise due to non-impact features, and easy forming of a color image by using a variety of color inks.
In such an ink-jet recording device, a recording sheet on which the recording head has performed recording is held by a platen in a recording area and is discharged by a discharge section disposed downstream in the transport direction of the recording sheet.
With reference to FIGS. 14 to 17, a known ink-jet recording device will be described. FIG. 14 is a perspective view illustrating the overall structure of a known ink-jet recording device 1. FIG. 15 is a sectional view illustrating the overall structure of the known ink-jet recording device 1. FIG. 16 is a perspective view schematically illustrating the positional relationship among a transport roller, a pinch roller, spurs, discharge rollers and so forth in the known ink-jet recording device 1. FIG. 17 is a sectional view schematically illustrating the positional relationship among the spurs, discharge rollers and so forth in the known ink-jet recording device 1.
As shown in FIG. 15, recording sheets P, as recording media, are stacked on a feeding section 2 and are fed sheet by sheet from the top of the stack by a feeding roller 22. The recording sheet P fed by the feeding roller 22 is supported by a transport roller 36 and a pinch roller 37 while being sandwiched therebetween and is transported to the start point of recording on a platen 34 by the transport roller 36 which is driven by a drive source (not shown).
A recording head 7 is detachably mounted on a carriage 50. The carriage 50 is movably mounted on a shaft 81 in a direction orthogonal to the transport direction of the recording sheet P. In other words, the recording head 7 performs recording while moving in a direction orthogonal to the transport direction of the recording sheet P.
A discharge roller shaft 41 is driven by a drive force of the transport roller 36 via a transmission roller 40. As shown in FIG. 16, the discharge roller shaft 41 has a plurality of discharge rollers 41a made from elastomer or gum mounted thereon for transporting the recording sheet P. Spurs 42 press-contacting the corresponding discharge rollers 41a have a sharp-edged periphery in order to minimize an amount of ink of a recorded image transferred to the spurs 42, since the spurs 42 come in contact with the recorded surface of the recording sheet P.
The recording sheet P is transported by the transport roller 36 and pinch roller 37 until the front end thereof is supported by the discharge rollers 41a and the spurs 42 while being sandwiched therebetween. After the rear end of the recording sheet P passes over the pinch roller 37, the recording sheet P is transported by the discharge rollers 41a and the spurs 42, and then is discharged and stored in a discharge tray 100.
The platen 34 has a plurality of projected ribs 34a formed on the upper surface thereof along the transport direction of the recording sheet P and supports the plurality of spurs 42, each disposed downstream of a corresponding projected rib 34a. Since the projected ribs 34a on the platen 34 and the corresponding spurs 42 are arranged on the same lines parallel to the transport direction of the recording sheet P in order to suppress the raised height of any cockled recording sheet P, wherein the cockling of the recording sheet P can occur when ink is applied on the recording sheet P, cockling having a concave shape is formed at every portion of the recording sheet between the adjacent projected ribs 34a, thereby minimizing the raised height of the cockled sheet lying in the recording area.
Such cockling is likely to occur especially when a permeable dye-type color ink is applied on the wide area of the recording sheet P. In the ink-jet recording device, the affect of the cockling must be eliminated and the gap between the recording sheet P and the recording head 7 must be maintained with the above arrangement in order to perform effective recording.
In recent years, a pigmentary black ink is used to increase black image density in the ink-jet recording device. The pigmentary ink requires a substantial time period for drying and fixing after the ink is applied on the recording sheet P. With this requirement, such pigmentary ink may cause a smear phenomenon in that a wet image formed on the previously discharged sheet is smeared by the currently discharging sheet because the front portion of the discharging sheet rubs the upper surface of the previously discharged sheet.
As shown in FIG. 15, a discharge section 4 of the recording device 1 has a discharge support 47 for preventing such smearing. The discharge support 47 supports the recording sheet that has been recorded, and extends the time period, from the applying time of ink on the recording sheet P to the arrival time of the recording sheet P at the discharge tray 100, for drying the ink applied on the previously discharged sheet.
In the known recording device 1, the platen 34 has the discharge support 47 that can be retracted therein. As shown in FIG. 15, the discharge support 47 usually retracts into the platen 34, and is pulled out and protrudes from the platen 34 at the time of recording. A plurality of the discharge supports 47 is disposed between the adjacent spurs 42.
While protruding from the platen 34, all the discharge supports 47 guide the recording sheet P upward higher than the surface of the recording sheet P lying in the recording area and support the discharging sheet P so that it bends downwardly at its central portion under its own weight. The known recording device 1 provided with the discharge supports 47 extends the time period from the recording time to the arrival time of the recording sheet P at the discharge tray 100.
However, in the known recording device 1 provided with the foregoing discharge supports 47, some of the discharge supports 47 raise the cockling in the recording area, thereby causing the recording sheet P to form a convex shape instead of a concave shape of the cockling between the adjacent spurs 42, and resulting in the substantially raised portions of the recording sheet P in the recording area. This causes the surface of the recording sheet P to come in contact with the recording head 7 or the carriage 50, giving rise to problems such that the surface of the recording sheet gets dirty or the recording head 7 is damaged.
The present invention can provide a recording device, provided with a discharge support, in which the parts of the device are easily fabricated, a large space for the discharge support is not needed, and a required flatness of the upper surface of the platen is easily obtained.
The present invention can also provide a recording device that comprises (a) a recording head for performing recording on a recording medium, (b) a support for supporting the recording medium downstream from the recording head in the transport direction of the recording medium, (c) a guide for supporting the support and (d) a holder for holding the guide. The guide protrudes from and retracts toward the holder substantially in the transport direction of the recording medium, and the support protrudes from and retracts toward the guide in a direction different from the protruding direction of the guide.
Further objects, features and advantages of the present invention will become apparent from the following description of the preferred embodiments with reference to the attached drawings.